// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : T98.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Disk image plugins.
//
// --[ Description ] ----------------------------------------------------------
//
//     Manages T98 disk images.
//
// --[ License ] --------------------------------------------------------------
//
//     This library is free software; you can redistribute it and/or modify
//     it under the terms of the GNU Lesser General Public License as
//     published by the Free Software Foundation; either version 2.1 of the
//     License, or (at your option) any later version.
//
//     This library is distributed in the hope that it will be useful, but
//     WITHOUT ANY WARRANTY; without even the implied warranty of
//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
//     Lesser General Public License for more details.
//
//     You should have received a copy of the GNU Lesser General Public
//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2018 Natalia Portillo
// ****************************************************************************/

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using DiscImageChef.CommonTypes;
using DiscImageChef.Console;
using DiscImageChef.Filters;
using Schemas;

namespace DiscImageChef.DiscImages
{
    public class T98 : IWritableImage
    {
        ImageInfo  imageInfo;
        IFilter    t98ImageFilter;
        FileStream writingStream;

        public T98()
        {
            imageInfo = new ImageInfo
            {
                ReadableSectorTags    = new List<SectorTagType>(),
                ReadableMediaTags     = new List<MediaTagType>(),
                HasPartitions         = false,
                HasSessions           = false,
                Version               = null,
                Application           = null,
                ApplicationVersion    = null,
                Creator               = null,
                Comments              = null,
                MediaManufacturer     = null,
                MediaModel            = null,
                MediaSerialNumber     = null,
                MediaBarcode          = null,
                MediaPartNumber       = null,
                MediaSequence         = 0,
                LastMediaSequence     = 0,
                DriveManufacturer     = null,
                DriveModel            = null,
                DriveSerialNumber     = null,
                DriveFirmwareRevision = null
            };
        }

        public string    Name => "T98 Hard Disk Image";
        public Guid      Id   => new Guid("0410003E-6E7B-40E6-9328-BA5651ADF6B7");
        public ImageInfo Info => imageInfo;

        public string Format => "T98 disk image";

        public List<Partition> Partitions =>
            throw new FeatureUnsupportedImageException("Feature not supported by image format");

        public List<Track> Tracks =>
            throw new FeatureUnsupportedImageException("Feature not supported by image format");

        public List<Session> Sessions =>
            throw new FeatureUnsupportedImageException("Feature not supported by image format");

        public bool Identify(IFilter imageFilter)
        {
            Stream stream = imageFilter.GetDataForkStream();
            stream.Seek(0, SeekOrigin.Begin);

            if(stream.Length % 256 != 0) return false;

            byte[] hdrB = new byte[256];
            stream.Read(hdrB, 0, hdrB.Length);

            for(int i = 4; i < 256; i++)
                if(hdrB[i]   != 0)
                    return false;

            int cylinders = BitConverter.ToInt32(hdrB, 0);

            DicConsole.DebugWriteLine("T98 plugin", "cylinders = {0}", cylinders);

            // This format is expanding, so length can be smaller
            // Just grow it, I won't risk false positives...
            return stream.Length == cylinders * 8 * 33 * 256 + 256;
        }

        public bool Open(IFilter imageFilter)
        {
            Stream stream = imageFilter.GetDataForkStream();
            stream.Seek(0, SeekOrigin.Begin);

            if(stream.Length % 256 != 0) return false;

            byte[] hdrB = new byte[256];
            stream.Read(hdrB, 0, hdrB.Length);

            for(int i = 4; i < 256; i++)
                if(hdrB[i]   != 0)
                    return false;

            int cylinders = BitConverter.ToInt32(hdrB, 0);

            imageInfo.MediaType = MediaType.GENERIC_HDD;

            imageInfo.ImageSize            = (ulong)(stream.Length - 256);
            imageInfo.CreationTime         = imageFilter.GetCreationTime();
            imageInfo.LastModificationTime = imageFilter.GetLastWriteTime();
            imageInfo.MediaTitle           = Path.GetFileNameWithoutExtension(imageFilter.GetFilename());
            imageInfo.Sectors              = (ulong)(stream.Length / 256 - 1);
            imageInfo.XmlMediaType         = XmlMediaType.BlockMedia;
            imageInfo.SectorSize           = 256;
            imageInfo.Cylinders            = (uint)cylinders;
            imageInfo.Heads                = 8;
            imageInfo.SectorsPerTrack      = 33;

            t98ImageFilter = imageFilter;

            return true;
        }

        public byte[] ReadSector(ulong sectorAddress)
        {
            return ReadSectors(sectorAddress, 1);
        }

        public byte[] ReadSectors(ulong sectorAddress, uint length)
        {
            if(sectorAddress > imageInfo.Sectors - 1)
                throw new ArgumentOutOfRangeException(nameof(sectorAddress), "Sector address not found");

            if(sectorAddress + length > imageInfo.Sectors)
                throw new ArgumentOutOfRangeException(nameof(length), "Requested more sectors than available");

            byte[] buffer = new byte[length * imageInfo.SectorSize];

            Stream stream = t98ImageFilter.GetDataForkStream();

            stream.Seek((long)(256 + sectorAddress * imageInfo.SectorSize), SeekOrigin.Begin);

            stream.Read(buffer, 0, (int)(length * imageInfo.SectorSize));

            return buffer;
        }

        public byte[] ReadDiskTag(MediaTagType tag)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorTag(ulong sectorAddress, SectorTagType tag)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSector(ulong sectorAddress, uint track)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorTag(ulong sectorAddress, uint track, SectorTagType tag)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorsTag(ulong sectorAddress, uint length, SectorTagType tag)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectors(ulong sectorAddress, uint length, uint track)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorsTag(ulong sectorAddress, uint length, uint track, SectorTagType tag)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorLong(ulong sectorAddress)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorLong(ulong sectorAddress, uint track)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorsLong(ulong sectorAddress, uint length)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public byte[] ReadSectorsLong(ulong sectorAddress, uint length, uint track)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public List<Track> GetSessionTracks(Session session)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public List<Track> GetSessionTracks(ushort session)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public bool? VerifySector(ulong sectorAddress)
        {
            return null;
        }

        public bool? VerifySector(ulong sectorAddress, uint track)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public bool? VerifySectors(ulong sectorAddress, uint length, out List<ulong> failingLbas,
                                   out                                   List<ulong> unknownLbas)
        {
            failingLbas = new List<ulong>();
            unknownLbas = new List<ulong>();
            for(ulong i = 0; i < imageInfo.Sectors; i++) unknownLbas.Add(i);

            return null;
        }

        public bool? VerifySectors(ulong sectorAddress, uint length, uint track, out List<ulong> failingLbas,
                                   out                                               List<ulong> unknownLbas)
        {
            throw new FeatureUnsupportedImageException("Feature not supported by image format");
        }

        public bool? VerifyMediaImage()
        {
            return null;
        }

        public List<DumpHardwareType> DumpHardware => null;
        public CICMMetadataType       CicmMetadata => null;

        public IEnumerable<MediaTagType>  SupportedMediaTags  => new MediaTagType[] { };
        public IEnumerable<SectorTagType> SupportedSectorTags => new SectorTagType[] { };
        public IEnumerable<MediaType>     SupportedMediaTypes =>
            new[]
            {
                MediaType.GENERIC_HDD, MediaType.Unknown, MediaType.FlashDrive, MediaType.CompactFlash,
                MediaType.CompactFlashType2, MediaType.PCCardTypeI, MediaType.PCCardTypeII, MediaType.PCCardTypeIII,
                MediaType.PCCardTypeIV
            };
        public IEnumerable<(string name, Type type, string description)> SupportedOptions =>
            new (string name, Type type, string description)[] { };
        public IEnumerable<string> KnownExtensions => new[] {".t98"};
        public bool                IsWriting       { get; private set; }
        public string              ErrorMessage    { get; private set; }

        public bool Create(string path, MediaType mediaType, Dictionary<string, string> options, ulong sectors,
                           uint   sectorSize)
        {
            if(sectorSize != 256)
            {
                ErrorMessage = "Unsupported sector size";
                return false;
            }

            if(!SupportedMediaTypes.Contains(mediaType))
            {
                ErrorMessage = $"Unsupport media format {mediaType}";
                return false;
            }

            imageInfo = new ImageInfo {MediaType = mediaType, SectorSize = sectorSize, Sectors = sectors};

            try { writingStream = new FileStream(path, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None); }
            catch(IOException e)
            {
                ErrorMessage = $"Could not create new image file, exception {e.Message}";
                return false;
            }

            IsWriting    = true;
            ErrorMessage = null;
            return true;
        }

        public bool WriteMediaTag(byte[] data, MediaTagType tag)
        {
            ErrorMessage = "Writing media tags is not supported.";
            return false;
        }

        public bool WriteSector(byte[] data, ulong sectorAddress)
        {
            if(!IsWriting)
            {
                ErrorMessage = "Tried to write on a non-writable image";
                return false;
            }

            if(data.Length != imageInfo.SectorSize)
            {
                ErrorMessage = "Incorrect data size";
                return false;
            }

            if(sectorAddress >= imageInfo.Sectors)
            {
                ErrorMessage = "Tried to write past image size";
                return false;
            }

            writingStream.Seek((long)(256 + sectorAddress * 256), SeekOrigin.Begin);
            writingStream.Write(data, 0, data.Length);

            ErrorMessage = "";
            return true;
        }

        public bool WriteSectors(byte[] data, ulong sectorAddress, uint length)
        {
            if(!IsWriting)
            {
                ErrorMessage = "Tried to write on a non-writable image";
                return false;
            }

            if(data.Length % imageInfo.SectorSize != 0)
            {
                ErrorMessage = "Incorrect data size";
                return false;
            }

            if(sectorAddress + length > imageInfo.Sectors)
            {
                ErrorMessage = "Tried to write past image size";
                return false;
            }

            writingStream.Seek((long)(256 + sectorAddress * 256), SeekOrigin.Begin);
            writingStream.Write(data, 0, data.Length);

            ErrorMessage = "";
            return true;
        }

        public bool WriteSectorLong(byte[] data, ulong sectorAddress)
        {
            ErrorMessage = "Writing sectors with tags is not supported.";
            return false;
        }

        public bool WriteSectorsLong(byte[] data, ulong sectorAddress, uint length)
        {
            ErrorMessage = "Writing sectors with tags is not supported.";
            return false;
        }

        public bool SetTracks(List<Track> tracks)
        {
            ErrorMessage = "Unsupported feature";
            return false;
        }

        public bool Close()
        {
            if(!IsWriting)
            {
                ErrorMessage = "Image is not opened for writing";
                return false;
            }

            int cylinders = (int)(imageInfo.Sectors / 33 / 8);
            writingStream.Seek(0, SeekOrigin.Begin);
            writingStream.Write(BitConverter.GetBytes(cylinders), 0, 4);

            writingStream.Flush();
            writingStream.Close();

            IsWriting    = false;
            ErrorMessage = "";
            return true;
        }

        public bool SetGeometry(uint cylinders, uint heads, uint sectorsPerTrack)
        {
            // Format uses fixed geometry for heads and sectors per track, cylinders must be calculated on closing.
            return true;
        }

        public bool WriteSectorTag(byte[] data, ulong sectorAddress, SectorTagType tag)
        {
            ErrorMessage = "Unsupported feature";
            return false;
        }

        public bool WriteSectorsTag(byte[] data, ulong sectorAddress, uint length, SectorTagType tag)
        {
            ErrorMessage = "Unsupported feature";
            return false;
        }

        public bool SetDumpHardware(List<DumpHardwareType> dumpHardware)
        {
            // Not supported
            return false;
        }

        public bool SetCicmMetadata(CICMMetadataType metadata)
        {
            // Not supported
            return false;
        }

        public bool SetMetadata(ImageInfo metadata)
        {
            return true;
        }
    }
}